Figure 2
From: Clinical relevance and biology of circulating tumor cells
Frequency of molecular markers expressed in circulating tumor cells of breast cancer patients. The shown frequencies are based on data from the literature [21, 26, 33, 42–53, 58, 59, 61–65, 75, 86–91] and they refer to the reported frequency (percentage of total number of circulating tumor cells (CTCs) detected in the particular report) of CTCs positive for the described marker. Markers for which there is more than one report are presented as the mean value and standard deviation of the available data in the literature. Abbreviations: ALDH1, aldehyde dehydrogenase 1; CK19, cytokeratin 19; EC, epithelial cell; EGFR, epithelial growth factor receptor; EMT, epithelial-mesenchymal transition; EpCAM, epithelial cell adhesion molecule; ERalpha, estrogen receptor alpha; Her-2, epithelial growth factor receptor type 2; HIF-1, hypoxia-inducible factor 1; MAGEA3, melanoma-associated antigen 3; MRP, multidrug resistant protein; Muc-1, mucin 1; p-EGFR, phosphorylated epithelial growth factor receptor; pFAK, phosphorylated focal adhesion kinase; PgR, progesterone receptor; PI3K, phosphatidylinositol 3-kinase; SC, stem cell; VEGF, vascular endothelial growth factor; ZEB1, zinc finger E-box-binding homeobox 1.